Thinking about a new iPhone battery, AMC Stubs A-List or need stamps? Buy them before 2019

In the holiday ads all month, you'll hear that the savings and discounts will "disappear soon" and are "for a limited time."

While that is certainly true for the new cars and heavily discounted big TVs, a few other companies have already announced which of their products will see prices rise once the calendar flips to 2019.

On the fence about replacing an old iPhone's battery, signing up for AMC's MoviePass rival or restocking your stamps? If you want to save some extra cash, you may want to make a decision sooner than later.

A new iPhone battery

Here's what to do if you find yourself in a pinch with a dying smartphone.(Photo: Getty Images / "juststock")

Is your iPhone slow or the battery weak, but you don't want to drop hundreds of dollars on a new device? A new battery could fix your problems.

After it was revealed last year that Apple was slowing down older iPhones due to aging batteries, the company announced it would be lowering the price of replacement batteries to $29 for 2018, allowing those with older phones that have been slowed down to get a second life.

Starting Jan. 1, however, those prices are going back up. Batteries for the iPhone 6 through 8 (including their Plus variations) that are out of warranty will soon jump from $29 to $49. The increase is even more notable for the iPhone X, which will now cost $69 instead of $29.

It is recommended to replace iPhone batteries when the batteries health falls below 80 percent. You can check the health of a battery on phones running iOS 11.3 (or later) by going to Settings then Battery and, finally, Battery Health.

From there, you will see the "maximum capacity" your battery is capable of compared to when it was new and whether it is strong enough to maintain operating at what Apple calls "peak performance capability."

It is common for batteries to lose charge and power as they age, particularly lithium ion batteries found in iPhones and most consumer electronics. Upgrading your battery now won't alleviate all the needs of a new phone, but if you're happy with what you have, it can help keep your current phone going a little longer.

AMC Stubs A-List

(Photo: AMC Entertainment)

MoviePass had an incredibly tempting proposition for consumers. A low monthly fee to see a movie a day in theaters. But now as 2018 comes to a close, the failing service is seemingly on its last legs.

For movie fans, however, a new option emerged: AMC's Stubs A-List.

For $19.95 per month (plus tax), you get to watch up to three movies a week. While $10 more than MoviePass and not offering a movie a day at any theater, AMC's program lets you see a movie in any format (including IMAX or Dolby Cinema) and you can reserve tickets.

In 2019, however, the company will be raising its rates by $2 to $4 a month in 15 states starting on Jan. 9. You can buy Stubs A-List now and lock in the cheaper rate for 12 months.

Whether a subscription movie service is right for you depends, of course, on how often you go to the movies, whether there is an AMC nearby, how much a ticket usually goes for in your area and whether there are movies coming out next year you'd want to see in a theater or in IMAX.

If it helps you decide, major blockbusters like "Captain Marvel," "The Lion King," "Toy Story 4" and "Avengers: Endgame" have already released their first trailers and teasers.

Forever stamps

The U.S. Postal Service is seeking to increase the price of its first-class stamp by 5 cents to 55 cents.(Photo: Kathy Willens, AP)

Nothing lasts forever, though Forever stamps get close. The price of postage, however, may rise again early in 2019.

If approved, the new rates would go into effect on Jan. 27. And, though price increases across industries often feel inevitable, the idea of Forever stamps adds an interesting wrinkle.

While seemingly not terribly pricey – the cost will rise from 50 cents per stamp to 55 cents – the 5-cent increase would be the biggest price hike since 1991. However, as their name suggests, Forever stamps will work in the future regardless of the price you pay for them today and irrespective of what increases will happen.

For those who use traditional mail, the savings of buying now could be worthwhile.